**Core Concept**
The patient's presentation of quadriparesis with an elevated CSF protein level and normal sugar and cell count is suggestive of Guillain-Barré Syndrome (GBS), a post-infectious autoimmune disorder characterized by demyelination of the peripheral nerves.

**Why the Correct Answer is Right**
In GBS, the immune system produces antibodies against the myelin sheath, leading to its destruction and subsequent nerve conduction block. The elevated CSF protein level is due to the breakdown of the blood-nerve barrier, allowing protein-rich material to leak into the CSF. The normal sugar and cell count help to rule out other causes of meningitis or encephalitis. The correct treatment for GBS is plasmapheresis, which involves the exchange of plasma with a replacement fluid to remove the autoantibodies and reduce inflammation.

**Why Each Wrong Option is Incorrect**
**Option A:** Corticosteroids are not effective in treating GBS, as the autoimmune response is not mediated by T-cells, which are the primary targets of corticosteroids.
**Option B:** Intravenous immunoglobulin (IVIG) is an alternative treatment for GBS, but plasmapheresis is generally considered the first-line therapy.
**Option C:** Antiviral medications are not indicated in GBS, as the condition is not caused by a viral infection.

**Clinical Pearl / High-Yield Fact**
GBS can occur after any infection, but it is most commonly associated with Campylobacter jejuni gastroenteritis.

**Correct Answer: B. Intravenous immunoglobulin (IVIG) is an alternative treatment for GBS, but plasmapheresis is generally considered the first-line therapy.